Paul Fierlinger wrote:I like this

-- the only worry might be that on smaller screens, while working with a single monitor, a split screen of two focuses might be too crowded. But particularly the idea of seeing both the project focus and timeline focus when needed sounds like a practical solution to all sorts of small problems.
well let's say that the current solution,docked tabs next to each other ,is still possible,but you could tear it off whenever you wanted to.
and with good gridlike,fast dockable solutions you shouldn't be bothered too much with resizing or moving stuff around.
For good examples watch toonboom or even Blender.
in blender right now you can add ,remove screens at any time and place in a smooth fashion. And when done,you can transform that screen in whatever you need it to be and/or remove it again (the removing is a bit hidden though). Timeline becomes canvas,canvas becomes preference settings,settings becomes xheet and so on. Check it out if you want to see what I mean,it's free,it's awesome.
Now toon boom does this a bit differently but it's mosty the same. One difference is that you can add tabs whereever you want. So not only do you make say: a canvas,timeline xsheet,main panel nicely nested into each other,you can Tab them=> switch from canvas to xheet,to effects panel to projects tab in a flash.
So basicly what we have not with project,timeline and xsheet,but fully how YOU want it. Rather put the xsheet and canvas on the same gridplace? you can.
In a case as this though,it is best to provide users with a reset to default button XD
Multiple programs already work like this in some way or another but Toonboom and blender do it best (imo). Now I'm not saying tvpaint should copy paste what they do,and change your interface to theirs. I'm saying,customizability is a good way to remove many of people's gripes with an interface because they have POWER over said interface. No more problems with big screens ,small screens,double or even triple monitors.
If this is in place,more focus can go to perfecting all the rest.